Internal combustion engines generate power necessary to accelerate and power vehicles. Generally, an oxidant (e.g., air) and a fuel (e.g., gasoline, diesel, natural gas, etc.) are combined in an engine cylinder and are ignited to generate the power necessary to drive the vehicle. Some gasoline powered engines require a substantially stoichiometric oxidant to fuel ratio in order to initiate the combustion reaction. Once initiated (e.g., spark ignited), the exothermic combustion reaction causes the temperature and pressure within the cylinder to increase, expanding the volume of the cylinder by thrusting the piston outward, thereby driving the crank shaft and powering the vehicle. One characteristic of an internal combustion engine is the torque rating of the engine, which relates to the engine's ability to accelerate and propel the vehicle.
Because the desired speed and acceleration of a vehicle are constantly changing, internal combustion engines are governed by control systems tuned to increase and decrease the torque production of the engine. In spark-ignited gasoline engines, conventional methods and strategies for controlling torque involve control loops that compare the desired engine torque with the actual torque output of the engine, and manipulate the air flow into the combustion chamber to reconcile the difference between desired torque and actual torque. For example, when a user presses the gas pedal to accelerate a vehicle or to manage conditions that the automobile may experience during travel, such as wind resistance, varying road conditions, varying weather conditions, road grade, size and weight of the automobile's cargo, etc., conventional control systems manipulate the injection of gasoline and the intake flow of air to the combustion chamber, thereby promoting or hindering the combustion process to respectively increase or decrease the amount of torque generated by the engine.
However, these conventional air control systems are often too slow and do not provide adequately fast response times for some torque requests. For example, some torque requests may be from secondary engine/car systems, such as anti-lock brake systems (ABS), traction control system (TCS), shift torque management (STM), etc., that limit the torque produced by the engine. For secondary engine systems to be effective, their torque requests must be effectuated in a timely manner. Generally, air intake systems cannot respond fast enough to the torque requests of such secondary engine systems. Accordingly, conventional engine torque governing systems relying on air control systems can lack the ability to precisely control torque production, which can lead to decreased engine performance and safety.